Mold for type casting machines



1951 J. J. CHRISTMAN ET AL 2,560,503

MOLD FOR TYPE CASTING MACHINES Filed Dec. 2, 1948 u B V V INVENTOR.

K BY 66m 0. KMPPEMW I I 5 V 4 the usual fashion and some of the metal always remains in the recesses for the next operation.

A further object of the invention is the provision of novel means whereby the terminals of the vents may be made larger than has heretofore proven satisfactory, thus venting the air more satisfactorily'and quickly. This desired result is achieved by virtue of the fact: that a perfectly clean mouthpiece after each casting cycle enables the molten metal to be maintained at a lower temperature. The metal being thus cast at a lower temperature is less fluid and the bleed vents can be larger while having a smaller amount of metal passing therethrough. This result is obtained with the harder alloys in a high degree and to only a slightly lesser degree with ordinary alloys. The slugs in all instances have a finer grain, a better and sharper face and porosity is a rarity.

In the drawing:

Fig. 1 is a transverse section taken through a metal pot, attached mouthpiece, and slugcasting mold and illustrating the present invention.

Fig. 2 is a broken section taken through the mouthpiece and mold of the present invention.

. Fig. 3 is a broken plan view of the face of the mouthpiece.

Fig. 4 is a broken plan view of a slug casting mold embodying the present invention.

Fig. 5 is a broken section taken through the mouthpiece and mold of :the present invention showing one type of recess in the mold. e Fig. 6 is a similarsection showing another type ofrecess in the mold. p Fig. 7 is a broken plan view of another type of recesses in the mold.

Referring now more particularly to the drawing, there is shown in Fig. l the-usual metal pot generally used in commercial type casting machines, the molten metal II contained therein being forced under pressure by means of a piston l2 through a delivery passage I3 in the throat section M. This throat section is fitted with the usual mouthpiece l having-a slightly raised face I6. v

-The mouthpiece is further provided with feed holes 20 communicating with the delivery passage 13. These holes are arranged in spaced relation and between the holes are the transverse vents 2]. The vents are generally triangular in transverse section and taper inwardly at their opposed terminals. The upper ends of the vents, when viewed as in Fig. 3, terminate short of the upper edge-22 of the raised face I6 and their lower. terminals 23 terminate at the lower edge 24 of the. raised face and, though narrow, they are sufficiently wide at such lower terminals to give approved air venting action. A slug casting mold 25 is formed with a longitudinal cavity 21 defined by walls 26 between which the slug is cast. It is further provided with suitable openings 38 for attachment to a rotatable disc (not shown). Suitable means (not shown) are provided for supporting a composed line of matrices 3| while the back face 32 of the mold-is-locked in sealed, face-to-face engagement with face It of the mouthpiece. The raised face l6 of the mouthpiece, except for the holes 20 and vents H is a perfectly smooth, planesurface. All the foregoing is conventional. The two portions 32 and 33 constituting the back face of the mold 25 are slightly raised above surfaces 34 and 35. 'Thesesurfaces 32 and 33 have heretofore been perfectly smooth, plane surfaces. I n accordance with the present-inven- 4 tion, however, they are provided with recesses 36 which are aligned with the vents 2| when the two members are in the face-to-face engagement of Fig. 1.

In Fig. 5 the recesses are shown as milled slots which are generally triangular in transverse section; whereas in Fig.. 6 the recesses 40 are slightly undercut and are of a dovetail contour. Also in Fig. 7 small holes 4! are provided instead of the transverse slots.

} In the event that the triangular milled slots 36 of Figs. 4 and 5 are employed the upper tervminals of the slots may be disposed at or near the upper ends of the vents 2| and in any event they should not extend as high as the upper edge 22 of raised face It of the mouthpiece when the members are in the position of Fig. 1. Similarly, the lower ends of the recesses should not extend down as far as the lower edge 24 of such raised face since this would give supplemental venting action and vents 2| adequately take care of this venting action.

v The same limitation with regard to length should be embodied in the dove-tail arrangement of Fig. 6. The width of the mold slots on the back face of the mold may vary from a width substantially the same as the width of the vents as shown in Fig. 5 to a somewhat lesser width as shown in Fig. 6 or to a still narrower width as shown in Fig. 4 compared to the vent widths shown in Fig. 3. In the event that the holes 4|- of Fig. '7 are employed the holes should be wholly confined in the areas defined by the several vents. The operation of the type casting machine is carried out in the same fashion as heretofore. When the slug is cast the mold is locked against the mouthpiece and the molten metal flows through the feed holes 20 in the mouthpiece and into cavity 21. As the cavity fills, the air bleeds through the lower ends of the vents. The metalalso fills the vents in the mouthpiece as well as the recesses in the back face of the mold. small quantity of the metal also passes through the lower ends 23 of thevents as the cavity becomes filled; v 4 After the metal has-solidified the mold leavesthe mouthpiece and every vent cast firmly adheres to the metal which is cast in the companionrecess in the mold. Since no metallic particlesremain in the vent openings the face ,-of.-,tlie mouthpiece is perfectly clean for the next operation. I

The excess metal is trimmed from the back of the mold in the usual fashion, which operation however, does not generally remove all the metal from the recesses. Even if such metal is removed during the. trimming operation it is of no conse: quencesince on the next cast the metal again enters the recesses and functions in the manner just described.'- 4 v v While three forms or'embodiments of the invention have been shown and described herein for illustrative purposes, and the construction and arrangement incidental to specific applica tions thereof have been disclosed and discussed in detail, it is to'be understood that-the invention is limited neither to the mere details. or relative arrangement of parts, nor to its specific embodiments shown herein, but that. extensive deviations from the illustrated formsor embodiments of the invention maybe made without departing from the principles thereof.

..;What.we.claim is:

1.: In 'a mold for a type casting machine having a type cavity. and wherein. the back face of the mold is arranged to be locked to a mouthpiece associated with a metalpot and having openings for delivery of the metal to the cavity, and air vents disposed between such openings, such back face having undercut recesses therein which are aligned generally with the air vents and which communicate with the mold cavity, the type metal being adapted to flow into and remain in such recesses and form a bond with metal cast in the vents to withdraw such cast metal upon departure of the mold from the mouthpiece.

2. In a mold for a type casting machine having a type cavity and wherein the back face of the mold is arranged to be locked to a mouthpiece associated with a metal pot and having openings for delivery of the metal to the cavity, and air vents disposed between such openings, such back face of the mold having spaced recesses therein which extend generally transversely from the mold cavity on each side thereof and which communicate with such mold cavity at their inner terminals, such recesses being generally aligned with the air vents, the type metal being adapted to flow into and remain in such recesses and form a bond with metal cast in the mold cavity and in the vents and to withdraw such metal cast in the vents upon departure of the mold from the mouthpiece.

3. A self-cleaning mouthpiece-mold assembly for type casting machines wherein the mold has a type cavity and the mouthpiece has openings JOHN JOSEPH CHRISTMAN. FREDERICK DAVID KLAPPROTH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 925,754 Converse June 22, 1909 1,696,074 Barber Dec. 18, 1928 1,897,012 Severin Feb. 7, 1933 OTHER REFERENCES The Intertype; A Book of Instruction for its Operation and General Maintenance, pub. by the Intertype Corp., 360 Furman St., Brooklyn 2, N. Y., copyright 1943, pgs. 82 and 83. (Copy in Div. 17.) 

